Joel (Carrey) and Clementine (Winslet) have always had a tumultuous relationship but Joel is shocked to find that Clementine has had all memories of their relationship erased. In order to forget the woman that he still loves, he decides to undergo the same highly experimental procedure. But as the painful memories are erased he begins to remember the passion and love they had for each other and so he tries to hide these memories in other parts of his brain...